The PS-InSAR Technique And Its Application To The Study Of Different Types Surface Deformation

In recent years, fast developing permanent scatterer SAR interferometry(PS-InSAR) overcome disadvantages of D-InSAR technology very well, such as loss ofspatial and temporal coherence, topographic errors, and the atmospheric effects.PS-InSAR technology focuses only the pixels (PS points) with stable back-scatteringcharacter in radar image, and the deformation magnitudes and patterns of those PSpoints are achieved by sequence steps of differential interferometry, phase unwrapping,and phase regression analysis. We can learn the deformation states of area of interestsby analyzing those highly coherent PS points.The detail principles and processing flows of the PS-InSAR and D-InSAR technique,components of interferometric phase are respectively introduced in this paper. Advancesabout PS-InSAR and D-InSAR technology at home and abroad over the past decade arereviewed. Three typical geological disasters, inter-seismic deformation of fault zone,city subsidence and landslide, are investigated by using the PS-InSAR monitoringtechnology, and taking respectively the Qilian mountain Haiyuan fault zone, AnyangCity of Henan Province and Zichang landslide area of Shanxi Province as study area.The study results are as follows：a）21frames of ENVISAT ASAR data spanning August2003to December2009are processed by applying PS-InSAR techniques to monitor trivial crustal deformationin the Qilian Haiyuan fault zone. The results show that the average displacement rate isup to-7mm/a~-9mm/a in Haiyuan County located in the north plate of Haiyuan faultfrom2003to2009, the cumulative relative LOS(line of sight) displacements reach-40mm~-60mm, and the direction is away from the satellite with a moving trend fromeast to west, which indicates the Haiyuan fault zone has a left-lateral strike-slipcharacteristics. The results are in good agreement with the ones from GPS and thetraditional geological methods obtained by other scholars.b）we processed11frames of ENVISAT ASAR data spanning March2008toDecember2009to study the subsidence of Anyang city, Henan province. The study areacovers the main city of Anyang and its western suburbs, Shuiye town area. The resultsachieved indicate that (1) Four districts including Long An, Yin Du, Bei Guan, WenFeng in Anyang city area got through subsidence due to groundwater extraction. Among of them, Wen Feng District is the largest subsidence area with most strong subsidencemagnitude. The average subsidence rate of Anyang city is-7mm/a~-38mm/a. Themaximum cumulative subsidence over the time of22months is-62mm;2)In thewestern suburbs of Anyang city, the subsidence happened in Shuiye town area becauseof underground mining. The average subsidence rate of this region is mainlyconcentrated between-12mm/a~-30mm/a and the maximum cumulative deformationreach-59mm.c）For the study of geological landslide deformation of zichang landslide area ofShanxi province, PS-InSAR techniques is also used to achieved displacement of thisarea by processing13frames ENVISAT ASAR data spanning May2009to September2010. The results show that three landslide regions, Huangchao Bay, Dongjia Templeand Liangjia Drainage, get through a certain deformation, and a quantitative analysis ispresented.